Embodiments of the present invention generally relate to filtering systems and more specifically to a system and method for filtering high frequency noise components generated by a power conversion unit.
Currently, output of pulse width modulated (PWM) power converters include large amount of high frequency noise components. It is undesirable to transfer the high frequency noise components to a load such as a motor, an inductive load, cable, or the like. In long cables, the high frequency noise components generate undesirable high amplitude voltage waves across the cables. Furthermore, in motors and inductive loads, the high frequency noise components cause stress in the insulations and generate high frequency leakage currents. In magnetic resonance imaging (MRI) devices, where the inductive loads such as gradient coils are excited by a gradient amplifier, the high frequency noise components affect the quality of an acquired image.
Traditionally, a passive filter is employed to filter the high frequency noise components. The passive filers use inductors, damping resistors, and capacitors. The passive filter is bulky due to the use of inductors, damping resistors, and capacitors. Further, the damping resistors introduce high losses. Furthermore, the passive filter is typically designed for a fixed value of frequency. Hence, use of such a passive filter to filter high frequency noise components having a plurality of frequencies is not feasible without further increasing footprint of the filter.
Accordingly, there is a need for an enhanced system and method for filtering high frequency noise components.